test/src/math/factorial/binomial_coefficient_prime_mod.test.cpp

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• Last update: 2024-01-30 20:57:42+09:00
• Problem: https://judge.yosupo.jp/problem/binomial_coefficient_prime_mod

Depends on

• 階乗テーブル (library/math/factorial.hpp)

Code

#define PROBLEM "https://judge.yosupo.jp/problem/binomial_coefficient_prime_mod"

#include <iostream>
#include <atcoder/modint>

using mint = atcoder::modint;

namespace atcoder {
    std::istream& operator>>(std::istream& in, mint &a) {
        long long e; in >> e; a = e;
        return in;
    }
    
    std::ostream& operator<<(std::ostream& out, const mint &a) {
        out << a.val();
        return out;
    }
} // namespace atcoder

#include "library/math/factorial.hpp"

int main() {
    std::ios::sync_with_stdio(false);
    std::cin.tie(nullptr);

    int t, m;
    std::cin >> t >> m;
    mint::set_mod(m);

    suisen::factorial<mint> fac(std::min(m - 1, 10000000));
    while (t --> 0) {
        int n, k;
        std::cin >> n >> k;
        std::cout << fac.binom(n, k) << '\n';
    }
}

#line 1 "test/src/math/factorial/binomial_coefficient_prime_mod.test.cpp"
#define PROBLEM "https://judge.yosupo.jp/problem/binomial_coefficient_prime_mod"

#include <iostream>
#include <atcoder/modint>

using mint = atcoder::modint;

namespace atcoder {
    std::istream& operator>>(std::istream& in, mint &a) {
        long long e; in >> e; a = e;
        return in;
    }
    
    std::ostream& operator<<(std::ostream& out, const mint &a) {
        out << a.val();
        return out;
    }
} // namespace atcoder

#line 1 "library/math/factorial.hpp"



#include <cassert>
#include <vector>

namespace suisen {
    template <typename T, typename U = T>
    struct factorial {
        factorial() = default;
        factorial(int n) { ensure(n); }

        static void ensure(const int n) {
            int sz = _fac.size();
            if (n + 1 <= sz) return;
            int new_size = std::max(n + 1, sz * 2);
            _fac.resize(new_size), _fac_inv.resize(new_size);
            for (int i = sz; i < new_size; ++i) _fac[i] = _fac[i - 1] * i;
            _fac_inv[new_size - 1] = U(1) / _fac[new_size - 1];
            for (int i = new_size - 1; i > sz; --i) _fac_inv[i - 1] = _fac_inv[i] * i;
        }

        T fac(const int i) {
            ensure(i);
            return _fac[i];
        }
        T operator()(int i) {
            return fac(i);
        }
        U fac_inv(const int i) {
            ensure(i);
            return _fac_inv[i];
        }
        U binom(const int n, const int r) {
            if (n < 0 or r < 0 or n < r) return 0;
            ensure(n);
            return _fac[n] * _fac_inv[r] * _fac_inv[n - r];
        }
        template <typename ...Ds, std::enable_if_t<std::conjunction_v<std::is_integral<Ds>...>, std::nullptr_t> = nullptr>
        U polynom(const int n, const Ds& ...ds) {
            if (n < 0) return 0;
            ensure(n);
            int sumd = 0;
            U res = _fac[n];
            for (int d : { ds... }) {
                if (d < 0 or d > n) return 0;
                sumd += d;
                res *= _fac_inv[d];
            }
            if (sumd > n) return 0;
            res *= _fac_inv[n - sumd];
            return res;
        }
        U perm(const int n, const int r) {
            if (n < 0 or r < 0 or n < r) return 0;
            ensure(n);
            return _fac[n] * _fac_inv[n - r];
        }
    private:
        static std::vector<T> _fac;
        static std::vector<U> _fac_inv;
    };
    template <typename T, typename U>
    std::vector<T> factorial<T, U>::_fac{ 1 };
    template <typename T, typename U>
    std::vector<U> factorial<T, U>::_fac_inv{ 1 };
} // namespace suisen


#line 21 "test/src/math/factorial/binomial_coefficient_prime_mod.test.cpp"

int main() {
    std::ios::sync_with_stdio(false);
    std::cin.tie(nullptr);

    int t, m;
    std::cin >> t >> m;
    mint::set_mod(m);

    suisen::factorial<mint> fac(std::min(m - 1, 10000000));
    while (t --> 0) {
        int n, k;
        std::cin >> n >> k;
        std::cout << fac.binom(n, k) << '\n';
    }
}

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